code: def __init__(self):
      super(TestCallback, self).__init__()
      self.on_preprocess_end_called_count = 0
      self.on_epoch_end_called_count = 0
      self.on_train_end_called_count = 0
  
file_path: cugraph/python/cugraph/cugraph/tests/layout/test_force_atlas2.py
imports: import time
  import pytest
  import cugraph
  from cugraph.structure import number_map
  from cugraph.internals import GraphBasedDimRedCallback
  from sklearn.manifold import trustworthiness
  import scipy.io
  from cugraph.datasets import karate, polbooks, dolphins, netscience, dining_prefs
label_desc: Use image node_id 1 to create a new TestCallback object from inherited base classes: GraphBasedDimRedCallback with example: obj = TestCallback()